Overcrowding May Decrease Cud Chewing

Dairy cows spend almost 8 hours daily chewing their cud for a total of almost 30,000 chews. When cows chew their cud or ruminate, they secrete saliva. This saliva contains a natural antacid which helps buffer the contents of the rumen or first compartment of the stomach. Proper buffering of the rumen allows a cow to digest forages better and to eat more feed which helps her produce more milk.

In a study at Cornell University, the scientists found that cows ruminated less when they were overcrowded at the feed bunk and freestalls by 30%. Overcrowded cows spent on average 28% of their time ruminating, whereas the uncrowded cows averaged 37% over a 24-hr time period. Thus, the cows in the overcrowded group ruminating 2 hours less, resulting in less saliva production and less buffering of the rumen contents.

Author: Donna Amaral-Phillips